Merge the svnserve-logging branch, in its entirety, to trunk, using the

Merge the svnserve-logging branch, in its entirety, to trunk, using the
following command:

  svn merge http://svn.collab.net/repos/svn/trunk@30530 \
            http://svn.collab.net/repos/svn/branches/svnserve-logging@30700

(svn merge --reintegrate does not handle renames on the branch)

See the branch for the details, but here is a summary:

- Add very simple --log-file functionality to svnserve, with no support
  for log rotation beyond simply killing the listener, rotating, and
  restarting.

- Move the logic for constructing the operational log line from all the
  places in mod_dav_svn where an operation is logged to the new svn_log__
  functions in libsvn_subr.

- Use svn_log__ functions to log operations in svnserve.

- Copy escape_errorlog_item from Apache 2.2.4 to new log-escape.c file,
  for escaping whatever random crap may be in logged error messages
  (e.g. newlines).

- Rename tools/server-side/svn_dav_log_parse.py and
  test_svn_dav_log_parse.py to tools/server-side/svn_server_log_parse.py
  and test_svn_server_log_parse.py and add support for svnserve format.

git-svn-id: http://svn.collab.net/repos/svn/trunk@30825 612f8ebc-c883-4be0-9ee0-a4e9ef946e3a